Seth Rogen Shares the Hilarious Story of How He Prepared for Knocked Up

Let's just say Seth Rogen wanted Knocked Up to be truly authentic. 

The actor and comedian recalled making some of the hit 2007 rom-com in Las Vegas, where he returned on Thursday night for an interview on Jimmy Kimmel Live!

As fans of the movie most likely remember, Rogen and Paul Rudd's characters head to Sin City, where they watch a Cirque du Soleil show while on hallucinogenic mushrooms. Rogen revealed that behind the scenes, director Judd Apatow had sent him and his executive producing partner to scout an actual show for that part of the movie. 

"As responsible producers, we thought the only appropriate way to really know which one would be the best would be to do shrooms for two days straight and see every single Cirque du Soleil show that was on the strip at the time, which we did, and it was amazing," he told Kimmel. 

As the star explained, they watched a water-themed show, which was terrifying to them while on drugs, as well as a sexy one, which is "just not right" on mushrooms. They settled on Mystère, the one ultimately featured in the film. 

However, there was one last hurdle to overcome—convincing a Cirque du Soleil creator to let them use the show in the way they wanted for the film.

Fortunately, it did not end up being a problem. "He was like, 'How do you think we come up with this stuff?'" Rogen recalled. "'That's how it was intended to be viewed.'"